The anhydride of 3,6-dioxaheptanoic acid has been described in PCT Publication WO-9103542 and Japanese Patent JP 90252800 as useful in formulations of mildew removers containing peroxide per acid materials.
The synthesis of thin film ceramic from metal organic acid salts (most usually aliphatic acids such as neodecanoic or 2-ethylhexanoic) is described in, for example, application Ser. No. 09/300,962, filed Apr. 28, 1999, entitled "Voltage Variable Capacitor or Varactor for High Frequency Power Modulator"; application Ser. No. 08/863,117, filed May 27, 1997, entitled "Process for Making Stoichiometric Mixed Metal Oxide Films"; J. V. Mantese et al, "Metalorganic Deposition (MOD): A Non-vacuum, Spin-on, Liquid-Based, Thin Film Method", MRS Bulletin, pp. 48-53 (October 1989); "Process for Fabricating Layered Superlattice Materials", PCT Publication WO 93/12538 (Applicant: Symetrix Corporation); U.S. Pat. No. 5,434,102, entitled "Process for Fabricating Layered Superlattice Materials and Making Electronic Devices Including Same", issued Jul. 18, 1995, to H. Watanabe et al; U.S. Pat. No. 5,439,845, entitled "Process for Fabricating Layered Superlattice Materials and Making Electronic Devices Including Same", issued Aug. 8, 1995, to H. Watanabe et al; and G. M. Vest et al, "Synthesis of Metallo-Organic Compounds for MOD Powders and Films", Materials Research Society Symposium Proceedings, Vol. 60 pp. 35-42 (1986).
The use of the anhydride of 2-ethylhexanoic acid to better control the reaction of metal alkoxides to metal salts is disclosed and claimed in U.S. Pat. No. 5,721,009, entitled "Controlled Carbon Content MOD Precursor Materials Using Organic Acid Anhydride", issued Feb. 24, 1998, to T. K. Dougherty et al.
A review of the need for environmentally-benign ceramic precursors and the alumina precursor made from 3,6-dioxaheptanoic acid and an alumina mineral (Group III precursor) is described by R. L. Callendar et al in "Aqueous Synthesis of Water-Soluble Alumoxanes: Environmentally Benign Precursors to Alumina and Alumina Based Ceramics", Chemical Materials, Vol. 9, No. 11, pp. 2418-2433 (1997).
A. W. Apblett et al, "Metal Organic Precursors to Yttria", Phosphorous, Sulfur, and Silicon, Vol. 93-94, pp. 481-482 (1994) disclose a Group III metal from yttrium acetate and the free acid including 2-ethyhexanoic acid and 3,6-dioxaheptanoic acid.
A. M. Bahl et al, "Heavy Alkaline Earth Polyether Carboxylates", Inorganic Chemistry, Vol. 36, No. 23, pp. 5413-5415 (1997) disclose calcium, barium, and strontium with 3,6-dioxaheptanoic acid from the free acid and the metal hydroxides.
In the last three references listed above, the 3,6-dioxaheptanoic acid salts are all made using either aqueous-based chemistry or a reaction in which water is a by-product. This may be the reason why the Group IV and V metal salts do not appear in the prior art. The present inventors show herein that the water causes gelling for these higher valence metals, and anhydrous techniques are therefore needed for these syntheses.